Abstract: The invention relates to the detection of the binding of analyte molecules, for example biopolymer molecules, to immobilized capture substance molecules. The invention consists in using semiconductor wafers (chips) with electrical circuits in spatial proximity to a surface area coated with capture substance molecules and loading the binding of the analyte molecules to the capture substance molecules with co-bound electrically conductive nanoparticles so that the nanoparticles can act upon the electrical circuits either through changes in the electrical stray capacitance or by generating electric currents, thus making the binding of the analyte molecules electronically detectable.

Abstract: The invention relates to methods for the measurement of fragment ion spectra in ion trap mass spectrometers in which fragment ions below a cut-off mass cannot normally be measured. The invention consists in measuring mass spectra including light fragment ions by briefly conducting the collisionally induced fragmentation—which is always brought about by a large number of collisions—at an unusual high RF storage voltage, which produces collisions more energetically than by conventional fragmentation, and then switching the RF voltage to a low RF voltage in a fast but controlled procedure. In this way light fragment ions are produced by double cleavages from metastable fragment ions with a certain half-life time. Since the cut-off mass for the storage capability is proportional to the RF storage voltage, reducing the RF storage voltage means that the light fragment ions can also be kept and measured in the ion trap.

Abstract: In a system for analyzing samples by mass spectrometry, analyte ions are analyzed first by field asymmetric ion mobility spectrometry (FAIMS) before being analyzed by a mass analyzer. The analyte ions are produced in an ion source operating at near atmospheric pressure and transferred via a dielectric capillary into the vacuum system of the mass analyzer. While passing through the capillary, the ions are analyzed by FAIMS via electrodes on the interior wall of the capillary.

Abstract: In an RF ion trap mass spectrometer, selected parent ions are fragmented by collisions or electrons and a spectrum of the ion fragments is measured. The measured fragment ion spectrum is then analyzed for the presence of a dominant ion species and, when a dominant ion species is present, selected parent ions are fragmented and a spectrum of the ion fragments is again measured, but with an additional collision excitation of the dominant ion species. The resulting daughter ion spectrum is qualitatively improved.

Abstract: A drift tube for an ion mobility spectrometer is assembled from stacked tube segments and has electrodes that generate an electric drift field and are electrically contactable from the outside of the drift tube. Most of the tube segments have at least two separate apertures so that, when the segments are stacked, these apertures form a drift region and at least one integrated gas channel both of which run parallel to the axis of the drift tube. At least one tube segment is inserted into the stack in which the two apertures are connected to form a gas channel transverse to the axis of the drift tube so that the drift region is connected to the gas channel at that tube segment.

Abstract: A digital audio signal processing system and method transforms two-channel stereo time-domain data into the frequency domain. Vector operations are performed upon the frequency-domain data by which signal components unique to one of the input channels are routed to one of the output channels, signal components unique to the other of the input channels are routed to another of the output channels, and signal components common to both channels are routed to a third and optionally to a fourth output channel. The frequency-domain output channels are then transformed back into the time-domain, forming an equivalent number of channels of output audio data. The vector operations are performed in a manner that preserves the overall information content of the input data.

Abstract: The invention relates to the automatic cleaning of ion sources inside mass spectrometers, especially the cleaning of ion sources where the ions are generated by matrix-assisted laser desorption (MALDI). The invention consists in cleaning the electrodes of the ion source, which are contaminated with organic material, in the mass spectrometer itself by etching with reactive ions produced by an electrically generated gas discharge in a specially admitted reactant gas.

Abstract: The invention relates to an ion mobility spectrometer in which a measuring tube, a filter and a transport device are connected to form a circulatory gas system, with a gas inlet which introduces ambient gas for analysis into the measuring tube of the ion mobility spectrometer. The invention involves connecting the measuring tube with the ambient gas by means of a dosing channel and connecting the circulatory gas system with the ambient gas by means of an outlet channel. The outlet channel joins the circulatory gas system between the high-pressure side of the transport device and the measuring tube, so that ambient gas for analysis is introduced into the measuring tube via the dosing channel while, at the same time, gas flows out of the circulatory gas system via the outlet channel without further transport devices being required.

Abstract: An ion source generates ions from analyte molecules which are desorbed from a sample on the surface of a sample support in a pressure range of approximately 30 to 300 pascal. Reactant ions are generated in a separate ion source and guided by ion guides to the point in front of the sample or to a reaction chamber in which the desorbed molecules are located. The reactant ions ionize the desorbed molecules to form analyte ions. The analyte molecules can be mixed in matrix material or adsorbed on the sample support surface without additives. The desorption can be continuous or pulsed, for example by light from lasers or diodes.

Abstract: The invention relates to methods and devices for regulating the filling level in measuring cells of ion cyclotron resonance mass spectrometers so that it is optimal for mass resolution and mass accuracy. The invention consists in supplying a fraction of the samples to a second reference mass spectrometer operated in parallel, and employing the mass spectra obtained from this reference mass spectrometer to regulate the filling level in the ion cyclotron resonance mass spectrometer.

Abstract: The invention relates to measuring methods and corresponding measuring cells for ion cyclotron resonance mass spectrometers (FTMS). The invention provides measuring methods with measuring cells, the ends of which each incorporate a large number of trapping electrodes, DC voltages of opposite polarities being applied across adjacent electrodes. For orbiting ions this builds up a repelling pseudopotential, which holds the ions in the measuring cell by reflection. This facilitates measurement of the image currents without the disturbing influence of RF voltages.

Abstract: A secure distribution system utilizes a content viewer that consists of an applet that is downloaded to a user's conventional browser when the user logs into a publisher's server. The content viewer requests a selected document from the server by referring to the document name or URL. The server retrieves the document and forwards it to the viewer in encrypted form. The viewer then computes a document identifier from the encrypted document and uses the identifier to request a key in order to decrypt the document. The key is forwarded from the server to the viewer that then decrypts the document and displays it in the viewer. Since the document is processed by the viewer and displayed only in a window associated with the viewer, none of the conventional browser functions has to be disabled. Further, since the document is downloaded in encrypted form, it cannot be stored or forwarded using the conventional browser.

Abstract: The invention relates to a mass spectrometric mixture analysis to determine both simple mass spectra of the substances as well as more detailed information about structures and other characteristics of the substances. The invention consists in temporally separating the substance mixture in a separating device, splitting the eluating flow of substances into at least two partial flows and measuring the substances in the different partial flows by mass spectrometry. A direct measurement provides a series of spectra whose evaluation is used for optimal control of the time at which a spectrum of another, delayed partial flow is acquired and the type of this measurement procedure. The substances of the delayed partial flows or their ions can thereby be chemically or physically modified in a variety of ways in order to provide the molecular weight as well as more detailed information.

Abstract: The invention relates to a method and apparatus for the fragmentation of large molecules, especially biopolymers. The invention consists in reacting analyte ions with excited or radical neutral particles, whereby, at least in the case of bombardment of analyte ions with helium atoms from an FAB generator, a new type of fragmentation occurs which strongly resembles fragmentation by electron capture (ECD). The reactions may be performed in magnetic ion traps (ion cyclotron resonance cells, ICR), in RF ion traps according to Wolfgang Paul, in RF ion guides, or in free beams of analyte ions or neutral particles.

Abstract: The invention relates to methods and instruments for ionizing analyte molecules, preferably biomolecules, which are dissolved in liquids or firmly adsorbed on surfaces. Liquids are nebulized at atmospheric pressure by electrospraying. Highly charged microdroplets, which enter the vacuum of the mass spectrometer through the inlet capillary, strike an impact plate when energy is fed in. The repulsive Coulomb force of the charges, the absorption of additional thermal energy and/or the conversion of their kinetic energy into thermal energy cause the microdroplets to burst and evaporate. Analyte molecules which are located in the nebulized liquid or on the impact plate are released in charged form and can be fed to the mass spectrometer for analysis by the extraction and collection effect of an ion funnel operated with RF and DC voltages.

Abstract: A small group of service providers, including specialists in various workplace issues, provides workplace services, such as human resource, legal, tax, accounting, environmental, financial, regulatory, governmental, technological, medical, consulting and marketing services to an organization by using a database of information concerning the organization and its contacts. An initial contact is made by a workplace resources office to the organization to gather background information on the contacts and the organization. The database is then initially populated with this background information. Later, when a situation arises that requires an answer to a specific workplace question, a contact places a telephone call to a specialist. The specialist accesses the database over a network and uses the pre-entered client-specific information to tailor advice to the specific question raised by the contact. The call and the response as categorized by the specialist are then stored in the database for later reference.

Abstract: The invention relates to methods and devices for the transport of ions generated in gases near atmospheric pressure into the vacuum system of a mass spectrometer. Instead of the single capillary customary in commercial instruments, the invention uses a multichannel plate with hundreds of thousands of very short and narrow capillaries, whose total gas throughput is no higher than that of a normal single capillary. The large-area take-up of ions in the gas flow greatly increases the transfer yield. If the channels are conductive, this prevents the inside surfaces becoming charged. An ion funnel can separate the ions from the gas flow in the vacuum and focus them. Gas-dynamic focusing in an electric decelerating field reduces ion losses caused by wall collisions and prevents very light ions (protons, water clusters) from entering the vacuum. Staged multichannel plates reduce pumping requirements.

Abstract: The invention relates to a method and instrument for the fragmentation of large molecular analyte ions, preferably biopolymer ions, by reactions between multiply charged positive analyte ions and negative reactant ions in RF quadrupole ion traps. Some of these reactions involve electron transfer reactions with subsequent dissociation of the biopolymer analyte ions, and some involve the loss of a proton, leading to stable product ions. The invention can use any type of ion traps, particularly three-dimensional RF quadrupole ion traps, for the reactions between positive and negative ions. The fragmentation yield can be increased because ions that remain stable as radical cations after transfer of an electron are further fragmented by collisionally induced fragmentation, forming fragment ions that are typical of electron transfer, and not those typical of collisionally induced fragmentation.

Abstract: Multiply-charged ions are generated from singly-charged ions of analyte substances. The singly-charged ions, which are supplied by many types of ion sources, are accelerated, together with donor ions of substances which have only a very low proton affinity, into a reaction cell. In the reaction cell, protons are transferred from the donor ions to the analyte ions to protonate the analyte ions and increase the ion charge. The multiply-charged analyte ions are subsequently fragmented by a variety of techniques and mass analyzed.

Abstract: The invention relates to the acquisition of mass spectra of complex protein mixtures, often called protein profiles, for example to search for biomarkers which indicate stress situations, or to identify microbes. Up to now protein profiles have been acquired using ionization by matrix-assisted laser desorption with high detection sensitivity in linear time-of-flight mass spectrometers, but these display very poor mass resolution and a very poor reproducibility of the mass values. The invention provides methods which produce surprisingly similar mass spectra, but with far higher mass resolution and mass accuracy. Ionization takes place outside the vacuum at ambient pressure, preferably by means of laser desorption and CI post-ionization. Analysis of the ions takes place in a high-resolution mass spectrometer, for example a reflector time-of-flight mass spectrometer with orthogonal ion injection.